The present invention broadly relates to coiling of strand or filamentary material into a container or can for storage or subsequent processing and, pertains more specifically to a new and improved method of filling a can with sliver which is coiled into the can by means of a pair of rolls. The present invention also relates to a new and improved apparatus for filling a can with sliver or the like.
It is known from prior art that can filling means comprise a so-called coiler plate provided with a conventionally S-shaped sliver guide tube by means of which the sliver is guided so as to be coiled into the can located beneath the coiler plate.
At the inlet of the sliver guide tube there is usually provided a pair of rolls or rollers which guides the sliver through the inlet orifice or port of the sliver guide tube into the latter and forwardly advances the sliver.
Such a can filling device is disclosed, for example, in German Published Patent Application No. 3,524,601, published Jan. 15, 1987. In this known device it is apparent that the sliver, immediately after leaving the outlet orifice or port of the sliver guide tube, is directly delivered into the can, i.e. upon the sliver layers or coils already present therein. Therefore, it is necessary for the sliver to be pulled out of the sliver guide tube by the rotation of the coiler plate relative to the sliver layers or coils in the can as well as by the friction between the sliver to be deposited in the can and the sliver already coiled therein. As a result, there is some drafting of the sliver within the sliver guide tube, and although such drafting is minor, it is not accurately defined. Differences in drafting resulting therefrom must be compensated during the subsequent sliver processing operations.
Another possible disadvantage of this known can filling device is that the sliver may expand in the sliver guide tube, resulting in additional friction therein. This is particularly possible in the case of slivers having a high synthetic or man-made fiber content.
To remedy the aforementioned drawback of the prior art construction, a second pair of rolls or rollers can be provided at the coiler plate as disclosed, for example, in German Patent No. 2,801,011, published May 23, 1979. This second pair of rolls or rollers pulls the sliver through the sliver guide channel. The axes of these rolls or rollers are substantially parallel to the axis of the coiler plate and thus substantially perpendicular to the latter.
This second prior art construction, which in fact constitutes an improved can filling device in relation to the first prior art construction hereinbefore discussed, still has the disadvantage of possible sliver drafting within the sliver guide tube and also the drawback that a second pair of driven rolls or rollers has to be provided. This roll or roller arrangement is relatively complicated and requires a corresponding constructional expenditure.